Multi-projectile warhead



Nov. 23, 1965 F'IG. 1.

(O8; ON W ATTORNEYS United States Patent O 3,218,976 MULTI-PROJECTILEWARHEAD Eugene L. Nooker, Silver Spring, Md., assignor to the UnitedStates of America as represented by the Secretary of the Navy Filed July8, 1960, Ser. No. 41,707 3 Claims. (Cl. 102-58) This application is acontinuation-in-part of patent application Serial No. 734,806, filed May12, 1958, and entitled Multi-Projectile Continuous Rod Warhead.

This invention relates generally to Warheads for missiles; moreparticularly, it relates to improvements in continuous rod Warheadstructures of the type shown in U.S. patent applications Serial Numbers590,077, 590,078, 590,079 and 734,806.

In copending patent application Serial Number 590,079 there is shown aWarhead including a projectile consisting of rods of rectangularcross-section arranged in layers and With their alternate opposite endsrigidly connected, so that When the Warhead is detonated, the projectileWill be propelled as a single continuous ring (continuous rod Warhead).Notwithstanding the best available fuzing, the single-shot probabilityof a single ring-type projectile striking a moving target at a point ofmaximum vulnerability is not as high as is desirable, due to variationsin the projectile itself, spatial approach conditions, and otherfactors. In an attempt to increase the probability of striking targetsof widely varying size and speed With available fuzing, amulti-projectile continuous rod Warhead has been proposed.

In copending application Serial Number 734,806 there is shown a Warheadutilizing a plurality of continuous rod ring-shaped projectiles which,following Warhead burst, will be spaced along the trajectory of a target(missile or airplane). Such a Warhead greatly increases the probabilityof moving targets of widely varying sizes, speeds, and trajectoriesbeing struck at a point of maximum vulnerability. The present inventionrelates to an improved Warhead design for obtaining the desired spacingof the ring-shaped projectiles.

It is, therefore, the principal object of this invention to provide amultiple-projectile, continuous rod Warhead so constructed that uponexplosion thereof a plurality of continuous rod projectiles Will bepropelled toward a target along spaced, substantially parallel paths sothat the probability of one or more of them striking a vulnerable pointon said target Will be substantially increased.

Another object of the invention is to provide a multipleprojectile,continuous rod Warhead having time-delay means to insure that theprojectiles Will be expelled so as to obtain a desired spacingtherebetween.

It is also an object of the invention to provide a multiprojectile,continuous rod Warhead employing means for assuring expulsion of saidprojectiles as continuous rings and without breakage of the rodsconstituting said rings.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection With the accompanying drawings, Wherein:

PIG. l is a diagrammatic view showing the manner in which a Warheadincorporating five projectiles functions to destroy relatively fast andslow and relatively large and small targets;

FIG. 2 is an axial section of a multi-projectile Warhead constructedaccording to the invention;

FIG. 3 is an axial section of a portion of a multiprojectile Warhead,showing one form of time delay plug;

FIG. 4 is an aXial section of a portion of a multi- 3218,976 PatentedNov. 23, 1965 projectile Warhead, showing a modified form of the timedelay plug of FIG. 3;

FIG. 5 is an aXial section of a portion of a multiprojectile Warhead,showing another form of time delay plug; and

FIG. 6 is an axial section of another embodiment of the invention.

In order to obtain maximum effectiveness from a multiple-projectile,continuous rod Warhead, it is proposed that the rod-type projectiles bepropelled outwardly along paths that are substantially parallel and thatare spaced apart a predetermined distance. In the present invention thespaced-apart relationship is obtained by individually expelling theprojectiles With a short time delay (of the order of a few milliseconds)between each expulsion. Because the missile carrying the Warhead ismoving during expulsion of the projectiles, the short time delay resultsin the projectiles traveling outwardly along spacedapart paths. Bycombining this time delay concept With a Warhead design Wherein eachprojectile is propelled outwardly at the same angle with respect to theaxis of the Warhead, the desired spaced-apart, substantially parallelprojectile paths are obtained.

Referring to the drawings, in FIG. l thereof there is showndiagrammatically at A a multi-projectile, continuous rod-type Warheadwhich consists of five rod-type projectiles arranged on a common axis,the direction of travel of a missile carrying the Warhead beingindicated by the arrow B. The position of the Warhead A at the time ofexpulsion of the first of the five rod-type projectiles is indicated atT1, the position at the time of subsequent projectile expulsions beingshown in broken lines, as indicated at T2, T3, T4 and T5. The continuousrod projectiles are shown in their Optimum extended positions (afterdetonation of their associated Warhead-contained explosive charges) atC1, C2, C3, C4 and C5, the path followed by the projectiles during theiroutward expansion being indicated by straight broken lines extendingbetween each projectile and the section of the Warhead from which itcame. The parallel arrangement of the paths which the projectiles followinsures uniform spacing between them at any point during their expansionto Optimum extended positions.

A relatively large target, such as a bomber aircraft, is showndiagrammatically at D in FIG. l. The position of the target D along itscourse is represented in full lines at D1, assuming that the target ismoving rapidly, and in broken lines at D2, assuming that it is movingrelatively slowly. Beneath the target D in FIG. l is a relatively smalltarget E, such as a guided missile. The position of a relatively fastmoving target E is shown at E1, Whereas a relatively slow moving targetE is shown at E2. From a study of FIG. ll it will be clearly seen that amultiple-projectile, continuous lrod Warhead, such as is indicated at A,would, if detonated at a point parallel to the trajectory of the targetD or the target E, intersect either of said targets, eithe-r fast orslow moving, With at least one of the projectiles C1 to C5. Thus, itWill 'be obvious that the employment of a multiple projectile Warheadconstructed as herein described Will avoid at least some of thepreviously indicated limitations of 'a continuous rod Warhead utilizingbut one continuous rod projectile.

Attention is now directed to FIG. 2, Wherein there is shown oneembodiment of the present invention. The Warhead of FIG. 2 comprises apair of generally cylindrical high explosive charges 2 and 4, thecharges shown being of the shaped type With hollow interiors, altho-ughit is to be understood that charges of other configurations may beemployed.

Surrounding the charges 2 and 4 are continuous rod-type` o projectiles 6and 8 which are of the kind disclosed in patent application SerialNumber 590,079, filed June 7, 1958, entitled Double Layer Warhead, Theprojectiles 6 and 8 are spaced from each other medially of the Warheadby an annular band of a material that is chemically inert with respectto the material of the charges 2 and 4, such as steel or glass fibers,which band also serves to anchor the corresponding inner ends of thesaid projectiles. The corresponding outer ends of the projectiles 6 and8 are retained in position by hoops 12 and 14,

of re'ctangular cross-section. It should be understood that the band 10and the hoops 12 and 14 are welded or otherwise suitably connected tothe confronting end faces of the rod elements 6 and 8 to thereby retainthe Warhead parts in assembled relationship, and that said hoops andband also cooperate to control the rod end portions so that, upondetonation of the Warhead, tum'bling or twisting of the rod elementswill be largely prevented and continuity of the projectiles will be thusmaintained. A thin liner 16 is shown Within the interior of the hollowcharges 2 and 4. The structure thus far descri'bed is similar to thatdisclosed in patent application Serial No. 734,806.

As is disclosed in said application, by proper design of the explosivecharges and the other elements of the Warhead the several projectilescan be made to expand along predetermined paths. Thus, in the subjectinvention, the Warhead can be so designed that the several projectileswill expand along parallel paths.

Positioned between charges 2 and 4, 'and under band 10, is a time delayplug, generally designated by broken lines at 18, the purpose of whichis to cause charge 4 to be detonated a short time after the detonationof charge 2. Disposed at the closed end of charge 2, and on the centralaxis thereof, is a detonator 20, which may be of any suitable type.

Disposed within the hollow 'interior of the charges 2 and 4, and lyingunder the time delay plug 18, is a wave and gas block 21. In the absenceof the block 21 the wave and gas effects emanating from the explosion ofcharge 2 might pass through the hollow interior of the Warhead and causethe premature detonation of charge 4, thereby by-passing the time delayplug 18. The block is employed to prevent such by-passing, and isconstructed of a material having a relatively low density. The specificconfiguration of the 'block for any particular Warhead is a matter ofdesign.

As has been explained hereinabove, the time delay plug 18 causes charge4 to be detonated a short time after the detonation of charge 2. Becausethe missile carrying the Warhead is moving during such detonation periodthe projectiles 6 and 8 will be expelled in spaced-apart relationship,thereby achieving maximum kill probability. More specifically, when themissile carrying the Warhead reaches the vicinity of a target a firingcircuit employ'ing a suitable infiuence type fuze, or other similardevice, will detonate the detonator 20, which in turn will detonatecharge 2 and thereby expell the projectile 6. The detonation of charge 2Would, in the absence of plug 18, also detonate charge 4 at almost thesame instant. However, the plug 18 is of a construction to cause thedesired time interval between the detonation of charges 2 and 4.

The time delay plug 18 may be of any of a number of constructions. Highexplosives such as are herein employed are normally of a type that aredetonated by intense local heat con'centrations, or shock Waves, orcombinations thereof. Thus, the time delay plug must be so constructedas to delay the action on charge 4 of such effects resulting from thedetonation of charge 2 as would cause the detonation of said charge 4.There are several possible ways in which the desired time delay can beobtained.

Three possible constructions for a time delay plug are illustrated inFIGS. 3, 4 and 5, respectively. In each of said views the charges 2 and4, the outer ring 10, the projectiles 6 and 8, the liner 16, and theblock 21 are 4 identical to those shown in FIG. 2. The time delay plug22 of FIG. 3 consists of a body, shaped as an annular ring, of amaterial which Will pass a shock wave at a rate slower than Would be thecase if the material were not present, i.e., if no time delay plug wereemployed. In FIG. 3 the detonation of charge 2 creates a detonation wavewh-ich impinges on plug 22, thereby establishing a shock wave in thematerial thereof. This shock wave is transmitted through the materialand impinges on charge 4, Where its effect is to create the shock and/or intense heat necessary to detonate said charge. The length of thetime delay between the detonation of charges 2 and 4 is determined bythe amount of time required for the shock wave to traverse the plug 22,which time in turn is determined by the dimensions and density of thematerial of the plug. Such materials as lead oxide and porous fuzedquartz are believed to possess the desired qualities.

A modified form of the time delay plug of FIG. 3 is shown at 24 in FIG.4, said plug consisting of an outer ring 26 and an insert ring 28. Thepurpose of the two element construction of the plug 24 is to make itpossible to obtain a variety of time delays by the use of but one plug.The material and thickness of the insert 28 may be varied to obtain thedesired time interval, the outer ring 26 functioning not only as apermanent, preset time delay, but also to maintain the elements in theirrespective positions regardless of the presence, absence, or of theparticular dimensions of the insert 28. The outer ring 26 can be of amaterial capable of causing the greatest time delay interval considerednecessary. If a lesser time interval is desired, the insert 28 may be ofa material causing less delay in the movement of the shock wave than iscaused by the material of ring 26. The Wave Will then pass through thematerial of insert 28 more quickly than through the material of ring 26,thereby causing detonation of charge 4 at a time earlier than Would bepossible with ring 26 alone.

Another manner of obtaining the desired time delay is to construct atime delay plug in such a manner and of such a material that thedetonation of the first charge will cause the material to be greatlyheated, or even melted, the hot material then, in turn, detonating asecond charge. In this instance the time delay occurs because of theshort period of time required for the material to heat and/or melt andto act upon the second charge. Such a time delay plug is shown in FIG. 5at 30, the plug consisting of an annular body 32 having a plurality ofbores 34 therethrough and annular recesses 36 and 38 in the outer endfaces thereof. The body 32 may be of any of a number of materials, suchas lead oxide, etc. 'The bores 34 are each filled with a relatively lowmelting point material 40. Disposed Within each of the recesses 36 and38 are deposits 42 and 44 of a material having the characteristic, upongnition, of rapidly burning With high heat. The action of the time delayplug of PIG. 5 is as follows. Detonation of charge 2 Will cause deposit42 to be ignited, said deposit reacting rapidly and producing high heat.The heat thus generated will melt the material 40, which will then, inturn, ignite deposit 44, the deposit 44 thereupon detonating charge 4.This procedure Will result in a time delay between charges 2 and 4, theprecise length of the delay, as above, being determined by thedimensions and materials of the time delay plug.

Although only two charges, and their associated projectiles, have beenillustrated, it is obvious that additional sets of charges andprojectles may be added to those shown, a suitable time delay plug beinginserted between each such set.

A modified form of the invention is illustrated in FIG. 6, wherein thereare employed high explosive charges 60, 62 and 64, projectiles 66, 68and 70, annular hands 72 and 74, hoops 76 and 78, a detonator 80, Waveand gas blocks 81 and 83, and liners 82 and 84, these elements being ofa construction similar to that of the corresponding elements in FIG. 2.In this modification of the invention the high eXplosive charge uponwhich the detonator first acts (the charge 60) is positioned between twoother charges of the Warhead (the charges 62 and 64), time delay plugs86 and 88 of any desired configuration being positioned between thecharges.

The Warhead of FIG. 6 functions in a manner similar to that of FIG. 2,the time delay plugs 86 and 88 causing the projectiles 68 and 70 to beexpelled at a suitable predetermined time after expulsion of theprojectile 66.

The present invention provides a Warhead of relatively simple mechanicalconstruction, only one detonator being necessary to obtain the desiredspaced expulsion of the projectiles of the Warhead.

In the Warhead configuration shown, the single detonator Will, Wheninitiated, detonate the high explosive charges of the Warhead in themanner already explained. Such detonation of the charges will cause theprojectiles associated therewith to be propelled outwardly as continuousrings, substantially as indicated at C1 to C5 in PIG. 1. The detonationof the charges Will, of course, break the ends of the rod elements fromtheir respective bands and hoops.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. A Warhead comprising a plurality of spaced hollow cylindrical highexplosive charges arranged on a common axis, said charges being open attheir confrontng ends, projectile structure surrounding each of thecharges, an annular band of material that is chemically inert Withrespect to the material of the charges, said band spacing the projectilestructures from each other and anchoring confronting ends of saidstructures, an annular time delay plug positioned between theconfronting ends of adjacent charges and disposed radially inwardly ofthe band, a detonator mounted in one of the charges, and a wave and gasblock mounted radially inwardly of the time delay plug and havingportions extending into said charges, said Wave and gas block being ofhollow cylindrical contour, said detontaor upon initiaton firstexploding the charge in which it is mounted and, after a time delayimposed by said plug, subsequently exploding an adjacent charge, saidWave and gas block guiding gases from the explosion of the charge firstexploded past the adjacent charge for preventing premature explosion ofsaid adjacent charge.

2. A Warhead as recited in claim 1, wherein said time delay consists ofan outer ring and an insert ring concentric with the outer ring, theouter ring being capable of imposin-g a predetermined relatively longtime delay for the passage of explosive forces between the charges, andsaid insert ring being capable of imposing a predetermined relativelyshort time delay in shock wave passage between the charges, said insertring permitting a shock wave to by-pass said outer ring.

3. A Warhead as recited in claim 1, wherein said time delay plugcomprises an annular body having a plurality of bores, said body havingrecesses at its opposite ends and communicating with the bores, adeposit of low melting point material in each of the bores, and adeposit of rapid burning, high heat producing material in each of therecesses.

References Cited by the Examiner UNITED STATES PATENTS 202,203 4/ 1878Urquhart 1112-69 X 424,482 4/1890 Justin 102-59 2,359,777 10/1944 Moore102-56 2,782,715 2/1957 Udry 1092-20 F OREIGN PATENTS 881 1863 GreatBritain.

BENJAMIN A. BORCHELT, Primary Examner.

ARTHUR M. HORTON, Examiner.

1. A WARHEAD COMPRISING A PLURALITY OF SPACED HOLLOW CYLINDRICAL HIGHEXPLOSIVE CHARGES ARRANGED ON A COMMON AXIS, SAID CHARGES BEING OPEN ATTHEIR CONFRONTING ENDS, PROJECTILE STRUCTURE SURROUNDING EACH OF THECHARGES, IN ANNULAR BAND OF MATERIAL THAT IS CHEMICALLY INERT WITHRESPEC TO THE MATERIAL OF THE CHARGES, SAID BAND SPACING THE PROJECTILESTRUCTURES FROM EACH OTHER AND ANCHORING CONFRONTING ENDS OF SAIDSTRUCTURES, AN ANNULAR TIME DELAY PLUG POSITIONED BETWEEN THECONFRONTING ENDS OF ADJACENT CHARGES AND DISPOSED RADIALLY INWARDLY OFTHE BAND, A DETONATOR MOUNTED IN ONE OF THE CHARGES, AND A WAVE AND GASBLOCK MOUNTED RADIALLY INWARDLY OF THE TIME DELAY PLUG AND HAVINGPORTIONS EXTENDING INTO SAID